Automatic regulator and regulating process for x-ray systems



Sept. 7 1926.

H. F. WAlTE AUTOMATIC REGULATOR AND REGULATING PROCESS FOR X-RAY SYSTEMS Filed Feb. 17 1922 g wgutoz Patented Sept. 7, 1926.

UNITED STATES PATENT OFFICE.

. HARRY F. WAITE, OF NEW YORK, N.

AUTOMATIC REGULATOR REGULATING PROCESS FOR X-R-AY SYSTEMS.

Application filed February 17,1922. Serial No. 537,192.

' vention, referenceis to be had tothe ac-.

companying drawings, forming a part hereor", in which the figure is a diagrammatic view of one embodiment of my invention.

IA system 1 embodying my invention is supplied with power from any suitable source, as an ordinary alternating current generator 2, which supplies power in the usual way to the line wires 3 and 4. The difference in potential between the wires 3 and 4 may be anything desired, as 110 volts.

A stepup transformer 5 has its primary 6. connected with the wires 3 and 4 by means of wires 7 and 8, the wire 8 passing through a'suitable regulator 9 of any desirable kind which may be used to regulateithe strength of the current in the primary 6. The secondary 10 of the step-up transformer 5 has two coils 11 and 12, respectively,which are connected in series through the magnet 13 of a relay, two wires 14 and 15 being employed for this purpose, and one of these wires, as the wire 15, is grounded at 16. The exterior wires of the coils 11 and 12 are numbered 17 and 18 and run to the anode 19 and cathode 20 of a hot cathode X-ray. tube 21 in the conventional manner.

The magnet 13 may be short circuited by two wires 22 and 23 which are connected to the wires 14 and 15 respectively, and these wires are connected through a rheostat 24 which is calibrated in milliamperes in amanner which will be described below. At this time, it is sufficient to say that this rheostat 24 throws more or le'ssresistance in shunt with the magnet 13 so that, the current flowing from this magnet 13 may be made stronger or weaker, as desired, for a purpose that will appear below.

The hot cathode tube 21 is heated by a current that passes over wires 25. and 26 which run from a small step-down transformer 27 which has its primary 28connected to the wire 4 by a wire 29 and to the wire 3 by a wire 30,a resistance 31 and a wire 32. This resistance 31 may be short circuited by means of a wire 33, a contact 34 of the relay 35, the armature 36 of this relay and a conductor 37. This relay 35 contains the magnet 13; above mentioned, and this armature may be arranged in any suitable way and in the preferred embodiment of my invenadjustably nounted coil spring 38, the ten- SIOH of which may be changed in the conventional manner by winding on a small Windlass 39. This magnet 13 may be sufficiently energized to overcome the tension oftlie spring 38 and draw the armature upon an insulated stop 40 and this will occur whenever the magnet 13 exceeds the strength indicated by the numerals on the rheostat :24 as will appear below.

' In view of the foregoing, the function and operation of my apparatus will be readily understood. Assuming that an alternating current is generated by the generator 2 and the system 1 is properly energized the regulator 9 is adjusted so as to give a current of the desired intensity in the primary 6 of the step-up transformer 5 and the handle of the rheostat 24 is placed according to the milliamperage desired in the tube 21. Let us say that ten vmilliamperes are desired in this tube and that the handle is placed for this strength of current. The secondary 10 of the step-up transformer 5 generates an X-ray generating current which passes through the conductors 17 and 18 in the conventional manner and also through the wires 14 and 15 andthe magnet 13, all of which are in series with the coils 10 and 12 of this secondary 10. The entire X-ray generating current which passes through the tube; '21 must pass through the conductors 14 and 15, but not all of this current will pass through the coil 13 because some of it will be shunted through the rheostat 24, the amount shunted depending upon the amount of resistance that is thrown in. hen the rheostat is set at 10 very little resistance is thrown in so that a very weak current will flow through the magnet 13. If a relatively strong current is desired in the magnet 13, a great deal of resistance is thrown in at the rheostat 24. As the X-ray tube operates and generates X-rays, the X-ray generating curtion itis normally spring supported by an that a smaller X-ray generating current will pass through the tube 21, and the result is that a smaller current will pass through the wires 24 and 25. This means that a smaller current will pass through the magnet 13 and then it is not strong enough to overcome the tension of the spring 38, the adjustment being such that it cannot, and then the circuit is closed at the contact 342 through the armature 36 and the resistance 31 is again short circuited. As soon as this resistance 31 is short circuited a stronger current will flow through the primary 28 of the transformer 27 and the current will build up until an X-ray generating current that is too strong passes through the tube 21. As soon as this occurs the magnet 13 is again energized, as above described. The resistance 31 is then restored to the circuit, as above set forth. and the hot cathode current is again reduced. These cycles'of operations are repeated indefinitely and with very great frequency so that a substantially uniform X-ray generating current passes through the tube 21 at all times, and this current will depend upon the adiustment of the rheostat 24. as above described.

It will be noted that the wire 15 is grounded so that the potential of the magnet 13 and the rhcostat 24 is nearly Zero with the result that the operator can handle this rheostat and adjust the same as much as he desires without the slightest danger of a shock, although the Xray generating current passing through the tube may have a tension of 200,000 to 300,000 volts or any other voltage that may be desired.

Furthermore, the regulator when once set requires no further attention of any kind by the operator so that he'is free to devote himself to his proper duties incidental to the use of the apparatus.

While I have shown and described one embodiment of my invention, it is obvious that it is not restricted thereto, but that it is broad enough to cover all structures and processes that come within the scope of the annexed claims.

Having thus described mv invention. what I claim is:

1. In a system of the class described, an X-ray tube of the hot cathode type, a two coil secondary for supplying an X-ray gen erating current to said tube, a relay with a magnet in circuit with said coils and between them and a rheostat for regulating the strength of the ct rrent passing through the magnet of the relay.

In a system of the class described, an X-ray tube of the hot cathode type with an X-ray generating current supplied to the same from a secondary of a step-up transformer, said secondary having two coils which are connected together through a magnet of a relay, a ground for one lead wire of said magnet and a rheostat in circuit with said magnet so that the strength of the magnet may be varied by the rheostat.

3. In a system of the class described, an X-ray tube of the hot cathode type with a secondary of a step-up transformer divided into two coils, a relay in said system with its magnet connected to said coils, a transformer for generating a hot cathode current and suitable connections including a resistance so that when the system is in use the resistance will be thrown in and out of circuit according to the action of the relay magnet.

4. In a. system of the class described, an X-ray tube of the hot cathode type with a secondary of a step-up transformer divided into two coils, relay in said system with its magnet connected to said coils, a transformer for generating a hot cathode current and suitable connections including a resistance so that when the system is in use the resistance will be thrown in and out of circuit according to the action of the relay magnet and a rheostat connected to the relay magnet.

5. In a system of the class described, an X-ray tube of the hot cathode type with a secondary of a step-up transformer divided into two coils, a relay in said system with its magnet connected to said coils, a transformer for generating a hot cathode current and suitable connections including a resistance so that when the system is in use the resistance will be thrown in and out of circuit according to the action of the relay magnet, a rheostat connected to the relay magnet and a ground for one of the wires leading to the relay magnet.

In testimony whereof, I have hereunto set my hand this 11th day of February,

HARRY F. vVAITE. 

